The present invention relates to the field of masonry units and, in particular, to masonry units for use in constructing dry stacked masonry walls and structures, and to methods of construction using such units.
Masonry construction of structures offers many advantages over traditional wood framing, including increased strength, fire resistance and insulation value. Traditionally, masonry construction techniques involved taking masonry units, typically manufactured cement, sand, water and aggregate, xe2x80x9cbutteringxe2x80x9d the units with mortar, typically mixed from cement, sand water and lime, and stacking the buttered units to form a number of courses. However, this technique has a number of disadvantages. First, the weakest part of such a masonry wall is the mortar joint, as the substitution of lime for aggregate reduces the overall strength of the joint. Second, the need to butter and precisely fit each block necessitates the use of skilled, and typically highly paid, masons. Finally, the mortar used to butter the units often hardens on the inside of openings within the blocks, preventing or hindering the insertion of insulation and/or reinforcements within the openings.
One solution to the lack of strength of mortar joints has been to dry stack the masonry units. In a typical dry stacked wall, the masonry units are stacked in a staggered arrangement and are reinforced by inserting steel rebar through interlocking holes. Once reinforced, a skin made up of a fiberglass and a cementicious material may be applied to the front and back faces of the walls to provide additional reinforcement. Adding the skin to the front and back faces of the wall increases the stability of the wall by up to ten times the stability of a wall without such a skin and provides an additional barrier to prevent cold and warm air from passing through the joints between masonry units. Therefore, the use of such a skin is preferred in these types of walls.
However, dry stacking of walls is not without drawbacks. First, like the staking of mortar walls, care must be taken to insure that the units are properly aligned with one another. This can be a painstaking process that greatly increases the time required to build such a wall. Second, the lack of motor in the joints between units allows air to easily pass through the joints and requires that a skin or other air barrier be used in connection with the walls. Third, the lack of mortar to hold the units in horizontal alignment make the use of many additional reinforcements, such as steel rebar, stabilizers, or the like, absolutely necessary in these types of walls.
A number of masonry units for dry stacked masonry retaining walls, such as those used for landscaping, erosion prevention, or the like, have been developed. Each of these systems utilizes a tab that extends downward from each unit and engages with the back side of the unit disposed below, causing the wall to be slightly angled backward toward the earth being retained. These masonry units work well in these applications, as the force of the earth upon the blocks counterbalances the backward lean of the wall, and the backward lean provides additional stability that could not be obtained in a straight wall without the use of xe2x80x9cdead menxe2x80x9d or other reinforcements. However, these units are not readily adapted for use in non-retaining walls, such as those used in structures, as the backward lean of produced by the stacking of the units makes these structures inherently unstable when they are not counterbalanced by the earth.
Therefore, there is a need for a masonry unit and masonry system that allow structures to be dry stacked without mortar, that allows masonry units to be quickly and accurately aligned during stacking, that does not require the use of separate stabilizers or other means for preventing deflection of the structure formed thereby, that produces substantially straight and stable walls, that retards the flow of air from one face of the wall to the other, that may be manufactured of a mixture of concrete and lightweight aggregate, and that will readily accept plaster or mesh substrates upon its outside surfaces without the need for sanding or special treatment.
The present invention is a masonry unit, masonry system and method of constructing a structure using the system. In its most basic form, the masonry unit of the present invention includes substantially parallel top and bottom surfaces, substantially parallel a front and back surfaces, and substantially parallel right and left surfaces. A locking ridge is disposed upon the top surface and extends along the top surface in substantially parallel relation to the front and back surfaces. A locking channel is disposed within the bottom surface and is dimensioned to mate with locking ridge on the top surface of an adjoining masonry unit. The locking channel is disposed inward from the bottom surface a distance that is a slightly larger than the distance from the top surface to the top of the ridge.
The preferred masonry unit has a web that is made up of at least two, and preferably five, central openings. These central openings are disposed in substantially perpendicular relation between said top surface and said bottom surface and extend through the masonry unit. The preferred masonry unit also includes two end openings that are disposed within said right surface and said left surface and likewise extend through the masonry unit in perpendicular relation with the top and bottom surface. The central and end openings allow the masonry unit to be significantly lighter in weight, easier to carry, and readily adapted for insulation. In addition, the preferred masonry unit is formed from a material comprising concrete and a lightweight aggregate material, which adds to the units"" weight and insulation advantages.
The preferred masonry unit is dimensioned to correspond to a standard 12xc3x978xc3x9716 inch sized block. Accordingly, the top and bottom surfaces form a rectangle having a length of about sixteen inches and a width of about twelve inches, the front and back surfaces of the preferred masonry unit form a rectangle having a length of about sixteen inches and a width of about eight inches, and the left and said right surfaces form a rectangle having a length of about twelve inches and a width of about eight inches.
In the preferred masonry unit, the locking ridge and locking channel are each disposed substantially along the centerline of the top surface and bottom surface respectively. The preferred locking ridge extends from the top surface a distance of about xc2xd inch and has a width of about 3⅝ inches, while the preferred locking channel extends into the bottom surface a distance of about ⅝ inch and has a width of about 3xc2xe inches.
In its most basic form, the masonry system for forming a structure, includes a plurality of primary masonry units of the present invention and a plurality of right and left corner masonry units. The right and left corner masonry units are mirror images of each other and are dimensioned for use at opposite ends of a structure. Each corner masonry unit includes a bottom, a top disposed in substantially parallel relationship to the bottom, an outer side, an inner side disposed in substantially parallel relationship to the inner side, a first end, a second end disposed in substantially parallel relationship to the first end, and a corner block portion extending outward from the inner side and forming a part of the first end. Each of the corner units also includes a locking ridge disposed across at least a portion of the top surface in substantially perpendicular relation to the outer side and the inner side, and a locking channel disposed across at least a portion of the top surface in substantially perpendicular relation to the outer side and the inner side. The locking ridge is dimensioned and positioned upon the top surface so as to mate with the locking ridge of the primary masonry units disposed above each of the plurality of right corner masonry units, and the locking channel is dimensioned and positioned upon the bottom surface so as to mate with the locking ridge of each of the plurality of primary masonry units disposed below each of the plurality of right corner units.
The masonry system is adapted to form a structure having an outer surface and an inner surface by stacking alternating courses of primary masonry units and right corner masonry units and courses of primary masonry units and left corner masonry units such that the locking ridges and locking channels of the primary masonry units and the right corner masonry units of one course mate with locking channels and locking ridges of primary masonry units and a left corner masonry units of adjacent courses.
In the preferred masonry system a skin of fiberglass and cementicious material is disposed upon the outer surface of the structure formed by the masonry system. The preferred system uses corner masonry units having corner block portions that extend outward from the inner side of the right corner block and the left corner a distance sufficient to allow the length of the first end to be substantially equal to a distance between the front surface and the back surface of the primary masonry unit.
Some embodiments of the system also include end masonry units the end masonry units are similar in all respects to the primary masonry units except that the locking ridge and locking channel do not extend fully to the end of the unit such that an intersection between the locking ridge and the channel is not visible when viewing the end masonry unit from the first end. In these embodiments, the masonry system is adapted to form a structure having an outer surface and an inner surface by stacking alternating courses of end masonry units, primary masonry units and right corner masonry units with courses of end masonry units, primary masonry units and left corner masonry units such that the locking ridges and locking channels of the end masonry units, the primary masonry units and the right corner masonry units of one course mate with locking channels and locking ridges of end masonry units, primary masonry units and, left corner masonry units of adjacent courses.
In the preferred masonry system, each of the primary masonry units, the right corner masonry units and the left corner masonry units further comprises at least two central openings disposed in substantially perpendicular relation between each top surface and the bottom surface, with the primary masonry units preferably having five central openings.
In its most basic form, the method of the present invention includes the steps of: obtaining a plurality of primary masonry units, right corner masonry units and left corner masonry units. Each of the plurality of primary masonry units, right corner masonry units and left corner masonry units have a first end, a second end, a top surface, and a bottom surface, and each having a locking ridge extending in substantially perpendicular relation to the first end in the second end along at least a portion of the top surface, and a locking channel extending in substantially perpendicular relation to the first end and the second end along at least a portion of the bottom surface. Once these specific materials are obtainined the next step involves stacking a base course including one of the right corner masonry unit and the left corner masonry unit and a plurality of primary masonry units. This stacking step includes disposing the first end of one primary masonry unit such that it abuts a second end of an adjacent primary masonry unit and such that the locking ridge and locking channel of one primary masonry unit is aligned with the locking ridge and locking channel of an adjacent primary masonry unit. Once the base course is stacked, the next step is to stack a second course comprising another of the right corner masonry unit and the left corner masonry unit and a plurality of primary masonry units. This stacking step involves disposing the first end of one primary masonry unit such that it abuts a second end of an adjacent primary masonry unit and such that the locking ridge and locking channel of one primary masonry unit is aligned with the locking ridge and locking channel of an adjacent primary masonry unit, and such that each of the locking channels of the second course mate with locking ridges of primary masonry units of the first course. Additional courses are then stacked in alternating relation to form the structure.
In some embodiments of the method a skin of fiberglass and cementicious material is applied to at least one of an outer wall and an inner wall of the structure. In others, the primary masonry units include at least one opening therethrough and the method further involves the steps of disposing insulation within the at least one opening of each of the plurality of primary masonry units.
Therefore, it is an aspect of the present invention to provide a masonry unit and system that allow structures to be dry stacked without mortar.
It is a further aspect of the present invention to provide a masonry unit and system that does not require the use of separate stabilizers or other means for preventing deflection of the structure formed thereby.
It is a further aspect of the present invention to provide a masonry unit and system that allows masonry units to be quickly and accurately aligned during stacking.
It is a further aspect of the present invention to provide a masonry unit and system that produces substantially straight and stable walls.
It is a further aspect of the present invention to provide a masonry unit and system that retards the flow of air from one face of the wall to the other.
It is a further aspect of the present invention to provide a masonry unit and system that may be manufactured of a mixture of concrete and lightweight aggregate.
It is a further aspect of the present invention to provide a masonry unit and system that may be easily insulated or reinforced after the structure has been built.
It is a further aspect of the present invention to provide a masonry unit and system that will readily accept plaster or mesh substrates upon its outside surfaces without the need for sanding or special treatment.
These aspects of the invention are not meant to be exclusive and other features, aspects, and advantages of the present invention will be readily apparent to those of ordinary skill in the art when read in conjunction with the following description, and accompanying drawings.